Experimental study on the ignition and combustion characteristics of KI-25# transformer oil under different heat radiation

This study investigates the combustion characteristics of KI-25# transformer oil under varying radiation conditions using a cone calorimeter experiment. Parameters such as ignition time, mass loss rate, heat release rate, total heat release, fire performance index, fire growth index, and other relevant factors were analyzed. The aim was to evaluate combustion behavior under different external radiation levels and initial fuel thicknesses. The results indicate that ignition time decreases with increasing external radiation, while the impact of oil thickness on ignition time is minimal but shows an overall upward trend. The mass loss rate exhibits a linear increase with rising radiation flux and initial oil thickness. Additionally, total heat release increases proportionally with oil thickness. Consequently, the fire performance index decreases, and the fire growth index rises, indicating an elevated fire risk index level. This study provides valuable insights for transformer fire safety practices and is crucial for enhancing power system safety.